Process for making continuous filament heather yarn

ABSTRACT

Doubled spun yarns having different dye receptivities are drawn simultaneously to the same degree, plied by filament intermingling, and wound on a package. This produces a heather type yarn.

United States Patent [19] Armstrong et al.

[54] PROCESS FOR MAKING CONTINUOUS FILAMENT HEATHER YARN [75] Inventors: Luther W. Armstrong; William A.

Rollings, both of Pensacola, Fla.

[73] Assignee: Monsanto Company, Saint Louis,

[22] Filed: Apr. 20, 1970 [21] Appl. No.: 29,981

[52] US. Cl. ..57/l57 S, 28/72.l2, 57/140 BY, 57/157 F [51] Int. Cl. ..D02g 1/16 [58] Field of Search..57/34 B, 140 BY, 157 F, 157 S; 28/1.4, 72.12

[56] References Cited UNITED STATES PATENTS 3,364,537 l/l968 Bunting, .lr., et al. ..2s/1.4

[451 Apr. 3, 1973 3,460,336 8/1969 Collingwood et a1. ..57/l40 BY 3,534,540 10/1970 Collingwood et al. ..57/140 BY 3,110,151 11/1963 Bunting, .112, et al. ..28/l.4 X 3,286,321 11/1966 Fletcher et a1 ....28/1.4 X 3,357,655 12/1967 lwnicki et ....57/157 F 3,400,194 9/1968 Boone et a1 ..28/72.12 X 3,426,406 2/1969 McCutchan, Jr "28 /1 .4

Primary Examiner-John Petrakes Attorney-Stanley M. Tarter, Kelly 0. Corley, Neal E. Willis and Elmer J. Fischer [57] ABSTRACT Doubled spun yarns having different dye receptivities are drawn simultaneously to the same degree, plied by filament intermingling', and wound on a package. This produces a heather type yarn.

2 Claims, 1 Dra ving Figure PATENTEDAPR 3 1975 INVENTQRS 1.. w. ARMSTRONG w. A. ROLLINGS The invention relates to a process for making a continuous filament heather yam. More particularly, it relates to a process for intermingling the filaments of two or more constituent yarns at the optimum point for assuring proper intermingling of the filaments.

Heather yarns and fabrics of staple fibers are well known in the art. When it was attempted to make heather yarns by combining (plying) continuous filament yarns having different dye receptivities, variable incomplete interming'ling or blending of the filaments of the constituent yarns at intermittent portions along the yarn led to locally visible loss of the heather effect. This improper blending is called phasing. Achieving uniform blending along the threadline is difficult. It will frequently be found that one of the constituent yams will tend to be largely in the center of the combined threadline at various locations along the yarn, the other constituent yarn being wrapped about it to form the undesirable phasing effect.

It has been discovered that phasing can be minimized or substantially eliminated by doubling (bringing together without twist) spun yarns, drawing them simultaneously in the same draw zone, and intermingling the filaments immediately after drawing and before winding. At this point the constituent filaments are exactly the same length and are under substantially the same tension expressed in grams per denier, which condition is difficult to uniformly achieve in other processes.

A primary object of the invention is to provide a process for making heather yarn from constituent continuous filament yarns having difierent dye receptivities.

A further object is to provide a process of theabove character wherein the filaments of the constituent yarns are blended to substantially the same degree along the entire threadline.

A further object is to provide a process of the above character wherein the constituent yarns are blended while the individual filaments thereof are under substantially the same tension.

Other objects will in part appear hereinafter and will in part be obvious from the following detailed description together with the accompanying drawing, wherein:

The FIGURE is a schematic perspective view of suitable apparatus for practicing the invention.

As shown in the FIGURE, spun yarn packages and 22 are positioned in creels for over-end withdrawal of yarn through separate guides 24. Yarn 26 from package 20 and yarn 28 from package 22 have different dye receptivities, although these constituent yarns may be of the same general polymer type (e.g., nylon). Yarns 26 and 28 are doubled (guided together in side by side relationship without twist) at guide 30, forming a doubled yarn 32. Yarn 32 passes from guide 30 over and behind upper nip roll 34 then between roll 34 and lower nip roll 36. Rolls 34 and 36 are positively driven to feed yarn 32 at a constant rate. Yarn 32 next passes in one or more wraps about drawpin 38, then in several passes about draw. roll 40 and its associated separator roll 42. Draw roll 40 is driven at a surface speed higher than the surface speed of nip rolls 34 and 36, to draw yarn 32. Pin 38 localizes the point at which drawing occurs, as is conventional.

Immediately after leaving draw roll 40 for the last time, doubled yarn 32 passes through a pneumatic intermixing chamber 44 wherein the filaments of the constituent yarns 26 and 28 are intermingled or interlaced with one another by a high-velocity air stream to form a plied yarn 46. The design of chamber 44 is not critical. After passing through chamber 44, yarn 46 passes through balloon guide 48 and is wound on bobbin 50 by a conventional ring and traveler mechanism 52. Although the plied yarn 46 could be wound without twist, a small amount of inserted twist is usually beneficial to the proper heather effect, and is therefore ordinarily preferred.

In the region wherein interrningling is accomplished, every filament is of the same length and is subjected to substantially the same tension in grams per denier. This permits substantially uniform intermingling along the entire length of yarn 46 and avoids the undesirable phasing effect.

EXAMPLE Spun nylon-66 yarn 26 of 229 denier was spun from a polymer formulated to resist acid dyes, while spun nylon66 yarn 28 of 193 denier was spun from a polymer formulated to enhance receptivity of acid dyes. The spun yarns were doubled, drawn, interlaced, and collected on bobbin 50 at a speed of 592 yards per minute. The draw ratio was 2.91, yielding a drawn deni er of 155. The resulting product gave an excellent heather effect with no visible phasing when knitted into mens hose and dyed in a dye bath containing both basic and acidic dyestuffs.

When it is attempted to form a heather yarn by plying separately drawn yarns, it is difficult to obtain proper intermingling uniformly along the. yarn, presumably because of tension variations.

The present process thus affords several advantages over the separate process. The equipment required is less, because only the intermingling chamber 44 and its air supply need be added to the existing drawing equipment. Equally importantly, the resulting product is more uniform along its length, and less susceptible to phasing.

We claim:

1. A continuous process for producing a heather yam, comprising:

a. doubling first and second continuous filament spun constituent yarns, said constituent yarns having different dye receptivities;

b. feeding said doubled yarn to a draw zone at a given c. withdrawing said doubled yarn from said draw zone at a speed higher than said given speed whereby said constituent yarns are drawn simultaneously to the same degree; v

d. immediately following said drawing step, intermingling the filaments of said constituent yams to produce a plied yarn; and

e. winding said plied yarn on a package.

2. The process definedin claim 1, wherein the draw point in said draw zone is localized. 

2. The process defined in claim 1, wherein the draw point in said draw zone is localized. 